Question

3 In triangle ABC, D and E are points on AB and AC respectively such that DE II BC and AD: DB = 2:3 IF AE = 6cm, then find EC.​

Answer 1

Given AD/BD=3/1

Using Basic proportionality theorem, In a triangle a line is drawn parallel to one side of a triangle and intersect the other two side at distinct points, the other two sides are divided in the same ratio.

In ΔABC⇒BDAD​=ECAE​⇒13​=EC6.6​⇒EC=2.2

Now AC=AE+EC

AC=6.6+2.2=8.8 cm